Treatment of Taste and Odor Compounds in Oklahoma Surface Water

Abstract

Taste and odor problems in drinking water have been addressed more and more by water utilities around the world. Consumer complaints must be considered by most drinking water treatment plants. A number of studies investigated that geosmin and 2-MIB are major compounds that cause these taste and odor problems in drinking water. The sources of geosmin and 2-MIB are cyanobacteria and actinomycetes. These two bacteria cause earthy and musty odor in drinking water. Although this unpleasant odor can be detected by consumers, currently, there are no regulations on geosmin and 2-MIB since these compounds are not threats to public health. The most successful treatment technologies used by most water treatment plants to remove geosmin and 2-MIB in drinking water are granular/powdered activated carbon (GAC/PAC), advanced oxidation processes (AOP), biofiltration, and other integrated systems. However, these methods are very expensive to install, maintain, and operate. For current and further studies, more efficient and economic taste and odor control technologies need to be addressed and investigated. Algaecides are used to stop the growth of algae; however, recent studies reported that the application of EarthTec, an example of algaecides, resulted in effective removal of geosmin and 2-MIB in drinking water. Also, Tulsa water treatment plant found that EarthTec has shown excellent abilities to remove these compounds in lakes. Therefore, this study investigated on algaecide removal of geosmin and 2-MIB in drinking water. Three experiments were conducted and compared. The results found that sorption and biodegradation in the study lake does not result in significant removal of geosmin and 2-MIB. The recommended EarthTec dosage and twice that dosage water samples without agitation found no significant contribution on the removal of geosmin and 2-MIB. However, the unfiltered lake water with EarthTec and agitation removed 76.58% geosmin and 78.64% 2-MIB, respectively, over 48 hours.